Rotary fluid pump



2 Sheets-Sheet 1 T. F. THOMPSON ROTARY FLUID FUMP INYENTOR. I T. F 'THDMP5DN ATTORNEY.

Filed March- 18, 1937 v Jan. 3, 1939.

v i v +3 .P a (MS Jan. 3, 1939. T. F. THoMPsdN Q 2,142,385

ROTARY FLUID PUMP I 2 Sheets- Sheet 2 ATTORNEY.

Patented Jan. 3, 1939 ROTARY FLUID PUMP Theodore F. Thompson, Des Moines, Iowa, assignor of fifty-one per cent to Don Raridon, Newton, Iowa Application March 18, 1937, Serial No. 131,600

1 Claim.

The principal object of this invention is to provide a rotary fluid pump of the cam type wherein the forcing element does not rotate and has the dividing 'vane attached thereto to prevent friction and to give a tight fluid seal.

A further object of my invention is to provide a fluid pump capable of delivering a great amount of pressure to the fluid line.

A still further object of this invention is to provide a rotary fluid pump of the eccentric type that is operated by asmall eccentric within the pumping element for increasing the leverage of the pump against the fluid.

Still further objects of my invention are to provide a rotary fluid pump that is economical in manufacture, durable in use, and eflicient in operation.

Theseand other objects will be apparent to those skilled in the art.

My invention consists in the construction, arrangement and combination of the various parts of the device, whereby the objects contemplated are attained as hereinafter more fully set forth, pointed out in my claim and illustrated in the accompanying drawings, in which:

Fig. 1 is a partial side sectional view of my complete rotary fluid pump.

Fig. 2 is an end sectional view of my rotary fluid pump and is taken on the line 22 of Fig. 1.

Fig. 3 is a side plan view of the eccentric drive shaft of my rotary fluid pump.

There are many types of eccentrically operated pumps on the market and one of the chief drawbacks to this type of pump is the use of friction vanes for sealing the pump between the inlet and outlet. These vanes are generally of fibre or other suitable material suspended within the housing of the pump and forced against the rotor of the pump by springs or like. As the rollers of these pumps generally rotate, considerable friction is induced in the pump and there is considerable wear on the end of the vane. Furthermore, fluid will leak past the vane and will get in behind it, rusting or otherwise damaging the spring. They are not tight and are of considerable hindrance to the use of high pressures in an eccentric pump. I have overcome these disadvantages as will be appreciated and as hereinafter more fully set forth.

Referring to the drawings, I have used the numeral ID to designate the cylindrical housing of the device having the usual base II and the end caps I2 and I3 suitably secured thereto as shown in the drawings. The housing It has a cylindrical opening therein in which the pumping unit operates. The numeral I 4 designates the pumping element of my device which is of general cylindrical construction and of a diameter smaller than the inside diameter of the housing I0. The numeral I5 designates the drive shaft rotatably mounted at each of its ends within bearing housings I5 and I1 and supported by roller bearings therein. These bearing housings I6 and I? are integrally formed on the end caps I2 and 53 respectively. Formed on the shaft I5 are the two eccentrics I8 and I9 which rotatably support the pumping element I4 through the roller bearings 20 and 2I respectively. Formed about each of the eccentrics I8 and I9 are bearing sleeves 22 and 23 respectively which are constructed of stainless steel or the like to further reduce the friction between the roller bearings and the eccentric drive and to eliminate corrosion. Cut in the upper end of the housing II] and in communication with its interior on either side of its longitudinal center is the inlet port 2t and the outlet port 25. Suitably secured to the top of the housing It is a second housing 26 having inlet and outlet ports 21 and 28 in communication with the inlet and outlet ports 24 and 25 of the housing II! respectively. Slidably mounted within a suitable bearing or slot 29 is the vane or blade 30 as shown in the drawings. This vane has a cylindrical tongue 3I formed along in its lower marginal edge for engaging a round groove out the longitudinal length of the pumping element I4. This vane 30 extends the full length of the pumping element I4 within the housing and the slot 29 is lined with stainless steel or similar material to prevent corrosion and allow the vane to reciprocate freely. I have used the numeral 32 to designate a one way by-pass valve between the upper inside portion of the slot 29 and the outlet 28 which is for the purpose of allowing any compressed fluid or air to escape to prevent compression of that material on the upward stroke of the vane 38. The numerals 33 and 34 designate the ordinary outlet pipes having their inside passageways in communication with the inlet and outlet ports 2'! and 28 respectively. The numeral 35 designates a ring seal on each end of the pumping element I4 as shown in Fig. 1 and by dotted lines in Fig. 2 of the drawings.

The practical operation of my device is as follows: The shaft I5 is rotated by a suitable source of power, thereby rotating the eccentrics I8 and I9, causing the pumping element I4 to move in an eccentric path in contact with the cylindrical opening within the housing I0. This draws the fluid, when the pump is rotated clockwise, through the intake pipe 33 the intake 21, intake 24, into the housing i where it is forced by the eccentric movement of the pumping element l4 about the cylindrical opening within the housing l0, thence out through the outlet 25. As the pumping element does not rotate within the device, the vane will follow the element 14 and pressure against the side of the vane 30% will cause it to seat more firmly in the groove in the element l4 preventing fluid from by-passing around the vane, thereby eliminating wear on the end portion of the vane 30'. Thus the vane or blade merely reciprocates back and forth and is semipivotally secured to the element Hi. There are no springs within the device and the pressure of the fluid against the vane 30 helps to seal it against by-passing fluid. Should there occur any by-passing of fluid or the like around the vane to a position above the upper end of the vane, it will be forced out through the by-pass valve 32 and thence into the outlet flow from the pump. Thus I have provided a rotary fluid pump of the eccentric type wherein the vane or blade is secured to the rotary pumping element eliminating the need for springs or the like, eliminating a frictionally engaging edge on the vane and providing a self-sealing contact or bridge between the housing of the pump and the pumping element.

Some changes may be made in the construction and arrangementof my improved rotary fluid pump without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claim any modified forms of structure or use of mechanical equivalents which may be reasonably included within its sco :e.

I claim:

In a pump, a housing having a cylindrical compartment, a cylindrical pumping element in said cylindrical compartment having an outside diameter less than the inside diameter of said cylindrical compartment, a slot in said housing communicating with said cylindrical compartment, an inlet passageway in said housing on one side of said slot and communicating with the inside of said cylindrical compartment, an outlet port in said housing on the other side of said slot communicating with said cylindrical compartment, a vane slidably mounted in said slot and pivotally secured at its inner end to said pumping element, a drive shaft rotatably mounted in said housing, an eccentric on said drive shaft rotatably supporting said pumping element,'a passageway in said housing having one end communicating with the inside of said slot at a point to the rear of said vane and its other end communicating with the inside of said outlet port, and a check valve imposed in said last mentioned passageway opening toward said outlet port.

THEODORE F. THOMPSON. 

